Now, to the shocking story aboard a carnival cruiseship. A 6-year-old drowned in one of the pools aboard that ship. Witnesses say it happened so fast, by the time they could get to them, it was too late. Matt gut hahn has the story. Reporter: This time, "the victory" is back at sea. The family of quentin hunter reeling from its heartbreak. They were on a cruise on sunday. Carnival officials say quentin was playing with his 10-year-old brother at this pool. When suddenly, eyewitnesses heard a dry for help. We heard the deejay say, there's a child in the pool. For a split second, he began to drown. Reporter: Passengers dove in after hunter, in the 4 1/2-feet deep pool. Passengers administered cpr, until its own medical team arrived. They stayed 20 minutes. He was fighting for his life. Reporter: On monday, that pool was crisscrossed with yellow caution tape. The company extended sympathy to the family. Last month, a 41-year-old man also died of an apparent drowning in the hot tub of another carnival ship. As for hunter, it's not clear how long he was under water. But experts say it's not unusual for a submerged body to go unseen. When the water is calm, you can see the dummy clearly. But when the water is agitated, the dummy is barely visible. There's no laws requiring cruise ships to post lifeguards at the pools. But carnival says this is the first time a child has drowned on one of its ships in company history. A health alert about the sports supplement called craze.

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